U.S. patent number 6,195,089 [Application Number 08/747,692] was granted by the patent office on 2001-02-27 for television graphical user interface having variable channel changer icons.
This patent grant is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Steve Blonstein, Jack Chaney, Kevin Harms, Keit Khauv, Fai-To Leung.
United States Patent |
6,195,089 |
Chaney , et al. |
February 27, 2001 |
Television graphical user interface having variable channel changer
icons
Abstract
A TV graphical user interface provided on a TV screen includes a
graphical channel changer for enabling a user to select a required
TV channel among about 1000 channels provided by a satellite TV
system. The graphical channel changer contains a vertical channel
bar composed of channel boxes that display numbers and logos of
selected TV channels. To switch a TV set to a required TV channel,
the user directs the pointing device at the graphical channel box
that indicates the required channel. Up and down scroll bars, that
allow the user to scan through the entire list of TV channels,
dynamically alter their size in accordance with the position of the
TV channel being currently scanned to provide the user with visual
feedback. A relative position indicator is arranged between the up
and down scroll bars.
Inventors: |
Chaney; Jack (Gilroy, CA),
Blonstein; Steve (Palo Alto, CA), Khauv; Keit (San Jose,
CA), Leung; Fai-To (Sunnyvale, CA), Harms; Kevin (San
Jose, CA) |
Assignee: |
Samsung Electronics Co., Ltd.
(Suwon, KR)
|
Family
ID: |
26697765 |
Appl.
No.: |
08/747,692 |
Filed: |
November 12, 1996 |
Current U.S.
Class: |
725/56; 348/563;
345/157; 345/158; 725/40; 725/45; 715/787 |
Current CPC
Class: |
H04N
21/47 (20130101); H04N 5/44513 (20130101); H04N
21/482 (20130101); H04N 21/4823 (20130101); H04N
21/4312 (20130101); H04N 2005/44556 (20130101) |
Current International
Class: |
H04N
5/445 (20060101); H04N 5/50 (20060101); H04N
7/173 (20060101); H04N 005/445 (); H04N 005/50 ();
H04N 007/173 () |
Field of
Search: |
;348/563,564,569,570,589,6,7,10,12,13,906 ;455/4.2,5.1,6.1,6.2
;345/158,157,145,146,348,352,341,327,342 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Powell; Mark R.
Assistant Examiner: Sajous; Wesner
Attorney, Agent or Firm: Sherman, Esq.; Kenneth L. Sherman
& Sherman Aiello; Jeffrey P.
Parent Case Text
This application claims the benefit of U.S. Provisional Application
No. 60/023,904 filed Aug. 14, 1996.
Claims
What is claimed is:
1. A television (TV) system comprising:
a CPU, and
a TV monitor controlled by said CPU for displaying a graphical user
interface (GUI) having at least one channel object for identifying
TV channels, and a control icon for changing the TV channels
identified by said channel object,
wherein said control icon dynamically varies its size with a change
of the identified TV channels to indicate the relative position of
a specific TV channel in relation to channels not currently
displayed on said channel object.
2. The system of claim 1, wherein said control icon comprises a
control bar that dynamically alters its size with a change of the
identified TV channels.
3. The system of claim 1, wherein said control icon comprises an up
scroll bar for scrolling up the displayed TV channels, and a down
scroll bar for scrolling down the displayed TV channels.
4. The system of claim 3, wherein activation of said up scroll bar
causes said channel object to identify a preceding TV channel
followed by a currently identified TV channel in a channel list
.
5. The system of claim 4, wherein activation of said down scroll
bar causes said channel object to identify a subsequent TV channel
following said currently identified TV channel in the channel
list.
6. The system of claim 5, wherein said up scroll bar and said down
scroll bar dynamically vary when said currently identified TV
channel is changed by said channel object.
7. The system of claim 5, wherein relative size of said up scroll
bar with respect to said down scroll bar dynamically varies when
said currently identified TV channel is changed by said channel
object.
8. The system of claim 5, wherein said up scroll bar shortens and
said down scroll bar elongates when said channel object replaces
said currently identified TV channel with said preceding TV
channel.
9. The system of claim 8, wherein said up scroll bar elongates and
said down scroll bar shortens when said channel object replaces
said currently identified TV channel with said subsequent TV
channel.
10. The system of claim 9, wherein said up scroll bar and said down
scroll bar extend beyond a safe area provided on a TV screen to
accommodate a picture to overscan conditions.
11. The system of claim 10, wherein said up scroll bar and said
down scroll bar stretch between opposite edges of the screen.
12. The system of claim 9, wherein said GUI further has a relative
position indicator arranged between said up scroll bar and said
down scroll bar for indicating position of the currently identified
TV channel relative to the channel list.
13. The system of claim 5, wherein said up scroll bar and said down
scroll bar are activated by a remote pointing device.
14. The system of claim 5, wherein said channel object indicates
numbers and logos of said TV channels.
15. A graphical user interface displayed on a screen of a monitor,
comprising:
at least one identification object for showing identification data
(ID), and
a control icon for changing the ID shown by said identification
object,
said control icon including first and second control objects that
dynamically and relatively vary in size with modification of the
shown ID in relation to IDs not currently displayed on the
screen.
16. The graphical user interface of claim 15, wherein said first
control object is activated for changing a currently shown ID to a
preceding ID that is followed by the currently shown ID in an ID
list.
17. The graphical user interface of claim 16, wherein said second
control object is activated for changing a currently shown ID to a
subsequent ID following the currently shown ID in the ID list.
18. The graphical user interface of claim 17, wherein said first
control object decreases in size and said second control object
increases in size when said identification object replaces the
currently shown ID with the preceding ID.
19. The graphical user interface of claim 18, wherein said first
control object increases in size and said second control object
decreases in size when said identification object replaces the
currently shown ID with the subsequent ID.
20. In a graphical user interface displayed on a TV monitor and
having at least one channel object for identifying TV channels, and
up and down scroll bars for enabling a user to change TV channels
identified by said channel object, a method of providing the user
with visual feedback, comprising the steps of:
decreasing the size of said up scroll bar and increasing the size
of said down scroll bar when said up scroll bar is activated to
replace a TV channel currently identified by said channel object
with a preceding TV channel followed by said currently identified
TV channel in a list of TV channels, and
increasing the size of said up scroll bar and decreasing the size
of said down scroll bar when said down scroll bar is activated to
replace said currently identified TV channel with a subsequent TV
channel following said currently identified TV channel in said list
of TV channels.
Description
TECHNICAL FIELD
The present invention relates to television (TV) systems, and in
particular, to a TV graphical user interface (GUI) having novel
channel changer bars that dynamically alter their size.
BACKGROUND ART
The growing availability of TV broadcast and interactive services
creates a need for a new type of a TV control system that would
facilitate user access to options offered by TV program providers.
For example, direct broadcast satellite services require users to
make their selection among about a thousand TV channels with
various TV programs and services. Direct television satellite
broadcasting is provided via direct broadcast satellites at an
uplink frequency of 17.3 to 17.9 GHz and a downlink frequency of
12.2 to 12.7 Ghz.
A digital satellite television system for direct television
broadcasting includes a transmitter for transmitting television
signals including video and audio components to a satellite. The
satellite retransmits the received television signals to an outdoor
antenna assembly that includes a dish-like antenna and a block
converter. The dish-like antenna directs the received television
signals to the block converter that converts the frequencies of the
received television signals to respective lower frequencies.
The television signals produced by the block converter are
connected via a coaxial cable to an indoor satellite receiver
coupled to a TV set. The satellite receiver tunes, demodulates and
otherwise processes the received television signals to provide
video and audio signals with a NTSC, PAL or SECAM format suitable
for processing by the TV set that produces an image on a display
screen in response to the video signals, and an audible response by
means of speakers in response to the audio signals.
Within the transmitter, analog video and audio signals are
converted to respective digital signals compressed according to the
Motion Picture Expert Group (MPEG) encoding standard. The resultant
digital signals are represented by a stream of packets including
error correction data. The type of packets is identified by a
header code. Packets corresponding to control data may also be
added to the packet stream.
In the MPEG standard, the video information may be transmitted in
the form of a luminance (Y) component and two color difference (U
and V) components. For example, the first color difference
component may represent the difference between the red image
information and the luminance image information (R-Y), and the
second color difference component may represent the difference
between the blue image information and the luminance image
information (B-Y). In addition, the color information is compressed
because the two color difference components correspond to more than
one picture element. The use of color difference components and the
sharing of the color difference components between picture elements
reduces the transmission bandwidth.
The digital information resulting from the compression and error
correction encoding is modulated on a carrier using Quaternary
Phase Shift Keying (QPSK) modulation and transmitted to a satellite
for retransmission.
The satellite receiver comprises a tuner for selecting the
appropriate carrier signal retransmitted by the satellite and for
converting the frequency of the selected carrier to an intermediate
frequency (IF) signal. A QPSK demodulator demodulates the IF signal
and supplies it to an error-correcting decoder to correct
demodulated packets representing video and audio information. An
MPEG decoder decodes and decompresses video and audio packets to
form digital video and audio signals supplied to a TV set. A TV
set-top box serves to deliver compressed digital video and audio
signals in real time usable form to one or more TV sets.
To facilitate user access to available TV programs and services, a
graphical menu, such as, a list of available TV channels, may be
displayed on a TV screen. To select a TV channel, a user may scan
through the TV channel list using, for example, control icons
displayed on the screen. Inasmuch as the digital satellite
television system may provide about 1,000 TV channels, it may be
hard to keep track of TV channels being scanned. Therefore, it
would be desirable to provide the user with visual feedback that
would indicate relative position of TV channels in the TV channel
list.
Further, due to "overscan" conditions, a television receiver may
produce a raster so that a picture on its screen may not be
entirely in the view of the user. To prevent data loss caused by
the overscan conditions, TV broadcast systems display images inside
a "safe" area located within approximately a 10% border all around
the edge of the screen.
In conventional TV systems, graphics data are generated so as to
position graphical objects, such as control icons, inside the safe
area to ensure that they appear on the screen even under the worst
overscan conditions. However, such an arrangement results in
reducing the size of graphical objects. This makes them difficult
to find and use. The channel list is actually a sequentially
ordered list. The order may be with respect to numerical channel
number or alphabetical by channel name. Generally, the entire list
is large and only some small subsequence of the entire list may be
displayed as selectable objects on the screen. It is the location
of this displayed subsequence within the full sequence that is
provided as graphical feedback to the user by means of dynamically
sizing the scroll bars.
Moreover, when there are no overscan conditions or overscan is less
than in the worst case, a blank band leaves between the safe area
and the edge of the screen.
Therefore, it would be desirable to keep graphical objects large
and to fully utilize the screen area independently of overscan.
DISCLOSURE OF THE INVENTION
Accordingly, one advantage of the present invention is in providing
a TV graphical user interface (GUI) having a visual feedback system
that indicates relative position of TV channels in a TV channel
list.
Another advantage of the present invention is in providing a TV GUI
having large graphical control objects.
A further advantage of the present invention is in providing a GUI
on a TV screen that fully utilizes the screen area independently of
overscan.
The above and other advantages of the invention are achieved, at
least in part, by providing a TV system that comprises a CPU, and a
TV monitor controlled by the CPU for displaying a graphical user
interface (GUI) having at least one channel object for identifying
TV channels. For example, the channel object may indicate numbers
and logos of the TV channels. A control icon is provided for
changing the TV channels identified by the channel object. The
control icon dynamically varies when the identified TV channels are
changed.
In accordance with a first aspect of the invention, the control
icon comprises an up scroll bar for scrolling up the TV channels,
and a down scroll bar for scrolling down the TV channels. For
example, the up and down scroll bars may be activated by a remote
pointing device. Activation of the up scroll bar causes the channel
object to identify a TV channel that precedes a currently
identified TV channel in a channel list. Whereas activation of the
down scroll bar causes the channel object to identify a TV channel
subsequent to the currently identified TV channel. The up and down
scroll bars dynamically vary when the channel object changes the
currently identified TV channel.
For example, the up scroll bar may shorten and the down scroll bar
may elongate when the channel object replaces the currently
identified TV channel with the preceding TV channel. By contrast,
the up scroll bar may elongate and the down scroll bar may shorten
when the currently identified TV channel is being changed to the
subsequent TV channel.
In accordance with another aspect of the invention, the up and down
scroll bars extend beyond a safe area provided on a TV screen to
accommodate a picture to overscan conditions. The up and down
scroll bars may stretch between opposite edges of the screen.
In accordance with a further aspect of the invention, a relative
position indicator is arranged between the up scroll bar and the
down scroll bar to indicate the position of the currently
identified TV channel relative to the channel list.
In accordance with a method of the present invention the following
steps are carried out to provide a user with visual feedback during
channel scrolling:
decreasing the up scroll bar and increasing the down scroll bar
when the up scroll bar is activated to replace a TV channel
currently identified by said channel object with a preceding TV
channel, and
increasing the up scroll bar and decreasing the down scroll bar
when the down scroll bar is activated to replace the currently
identified TV channel with a subsequent TV channel.
Still other objects and advantages of the present invention will
become readily apparent to those skilled in this art from the
following detailed description, wherein only the preferred
embodiment of the invention is shown and described, simply by way
of illustration of the best mode contemplated of carrying out the
invention. As will be realized, the invention is capable of other
and different embodiments, and its several details are capable of
modifications in various obvious respects, all without departing
from the invention. Accordingly, the drawings and description are
to be regarded as illustrative in nature, and not as
restrictive.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a block diagram of a satellite receiver of the present
invention.
FIG. 2 is a block diagram illustrating a graphical object drawing
procedure.
FIG. 3 illustrates contents of a color look up table.
FIG. 4 is a flow chart illustrating an example of interactions
between a CPU and graphics accelerator.
FIG. 5 is a diagram illustrating arrangement of pixels on a TV
screen.
FIG. 6 is a diagram illustrating the GUI on the TV screen in
accordance with the present invention.
FIG. 7 is a flow chart that illustrates operations carried out in
accordance with the present invention to dynamically change the
sizes of the up and down scroll bars.
BEST MODE FOR CARRYING OUT THE INVENTION
The best mode for practicing the invention is based on the
realization of a satellite receiver in a digital satellite
television system. However, it is to be understood that the present
invention is applicable to any system for receiving TV signals.
Reference is now made to FIG. 1 of the drawings wherein an indoor
satellite receiver 300 includes an analog radio-frequency (RF)
tuner 302 such as a satellite front end demodulator manufactured by
Sharp/Comstream. The RF tuner 302 is coupled via an external
UHF/VHF to an outdoor unit that receives incoming television
signals from a satellite. The outdoor unit may comprise a 18"
antenna made of aluminum and dual low noise block converters that
convert satellite signals in a frequency range from 12.2-12.7 GHz
received by the antenna into the 950-1450 Mhz frequency range
signals.
The RF tuner 302 equipped with a local oscillator and mixer selects
the appropriate carrier signal corresponding to a selected
satellite TV channel from the 950-1450 Mhz signals received from
the outdoor unit. The frequency of the selected carrier is
converted to an intermediate frequency (IF) signal fed to an
analog-digital converter 304 that produces a digital IF signal.
A digital demodulator 306 performs QPSK demodulation of the digital
IF signal and carries out multiple error correction algorithms
required to decode error correction data contained in the received
signal. For example, Viterbi and Reed-Solomon error correction
algorithms may be employed. A single ASIC manufactured by Comstream
may be used as the digital demodulator 306.
The decoded digital signal is fed to a transport chip 308
responsible for demultiplexing video, audio and data signals. The
transport unit 308 is also connected to a card 310 for providing
conditional access to the satellite receiver 300. The card 310 such
as a Smart Card manufactured by the News Data Corporation controls
access to paid channels and services using the Data Encryption
Standard (DES).
Wideband data are fed to the transport unit 308 via a wideband port
312 that provides compatibility with 16:9 wide NTSC format. The
wideband port is also controlled by the conditional access system.
A buffer 314 is used to support the transport chip operations. A
128K.times.8 static random-access memory (SRAM) with access speed
of 70 ns may be used as the buffer 314.
The transport chip 308 routes the video and audio signals to an
MPEG decoder 316, while data is made available to a CPU 318. The
MPEG decoder 316 provides decompression of the video and audio
signals in accordance with the MPEG standard. For example, a
single-chip STi3520MPEG decoder may be used. By way of example,
reference is made to U.S. Pat. No. 5,198,901 to Lynch of Mar. 30,
1993; to U.S. Pat. No. 5,293,229 to Iu of Mar. 8, 1994; to U.S.
Pat. No. 5,311,310 to Jozawa et al. of May 10, 1994; to U.S. Pat.
No. 5,361,105 to Iu of Nov. 1, 1994; to U.S. Pat. No. 5,386,234 to
Veltman et al. of Jan. 31, 1995; and to U.S. Pat. No. 5,400,076 to
Iwamura of Mar. 21, 1995. Those disclosures and citations
referenced therein may be consulted for an understanding of the
specific details of conventional MPEG decompression
arrangements.
The MPEG decoder 316 of the preferred embodiment is supported by a
synchronous RAM 320 formed by four 256K.times.16 DRAMs with access
speed of 70 ns capable of holding 3 full frames of MPEG video and
audio data, and control information.
Decompressed video data in YUV format is fed to a digital video
encoder 322. The decompressed audio data is supplied to the video
encoder 322, and to a stereo audio digital-to-analog converter
(DAC) 324 for converting digital audio signals into analog form. A
single-chip AK4319 DAC manufactured by Asahi Kasei may be used as
the DAC 324.
Operations of the satellite receiver 300 are supported by the CPU
318 such as a Motorola 68340 CPU chip running at 16 MHz. An
external watch crystal is used to derive the 16 MHz internal clock.
The CPU 318 may have a 16-bit external data bus, and a 32-bit data
bus for internal operations. The CPU 318 may run the PSOS+
operating system developed by Integrated Systems Inc.
The CPU 318 is supported by a ROM 324, a SRAM 326, and an EEPROM
328. The ROM 324 that holds the PSOS+ operating system, menus,
fonts, and other fixed data may be formed by two 4Mbit masked ROM
chips organized as 512K.times.8 with access speed of 95 ns.
The SRAM 326 formed, for example, by two 1Mbit SRAM chips organized
as 128K.times.8 with access speed of 70 ns, may be used for storing
all active data such as system stacks, variables, menu data, etc.
The ROM 324 and SRAM 326 may operate at a zero wait state to
provide maximum performance.
The EEPROM 328, for example, a single 8K.times.8 EEPROM chip with
access speed of 150 ns, may store non-volatile data such as user
preferences.
To enhance the graphics presentation capabilities of the satellite
receiver 300, a graphics accelerator 330 such as a MCD212 graphics
accelerator manufactured by Motorola is used as a co-processor. The
graphics accelerator 330 allows the receiver 300 to increase the
rate of screen updates and to provide up to 256 colors in a
graphics image. Also, the accelerator provides graphical effects
such as wipes, dissolves, fades, etc. during transitions of menus
on a TV screen, and supports operations of a remote pointing device
such as an Airmouse.RTM.. This type of remote pointing device is
manufactured by Seletech and Airmouse Remote Controls. The output
of the graphics accelerator 330 produced in RGB format is fed to a
converting circuit 332 for conversion into YUV format.
The graphics accelerator 330 may be supported by a synchronous
4Mbit RAM 334 provided, for example, on a single 256K.times.16
lDRAM chip with access speed of 70 ns. The RAM 334 used for storing
graphics data is capable of storing two graphics planes with
720.times.480 pixel resolution. The graphics accelerator 330 allows
two graphics planes to be combined to produce various graphical
effects.
The graphics data from the conversion circuit 332, and decompressed
video and audio data from the MPEG decoder 316, are supplied to
separate inputs of the digital video encoder 322 such as a
single-chip Phillips 7184 encoder. The video encoder 322 is
responsible for encoding digital video, audio and graphics data to
produce a combined composite signal in NTSC format. For example,
U.S. Pat. No. 5,489,947 to Cooper of Feb. 6, 1996, incorporated
herewith by reference, discloses on screen display (OSD)
arrangement that allows the graphics data to be displayed on a TV
set screen together with the image represented by the received
video signals, or in place of this image. A single control bit may
be used by the video encoder 322 to switch its output from graphics
data to video and back.
The video encoder 322 also produces baseband video and audio
signals. The baseband video signals are buffered by a pair of video
operational amplifiers 336 coupled to video connectors. The
baseband audio signals are fed to the stereo audio DAC 324 for
converting to analog format and supplying to audio connectors. The
video and audio connectors may be coupled to such external devices
as stereo receivers, TVs or VCRs.
The combined composite signal from the video encoder 322 may be fed
to a NTSC modulator 338 that modulates the composite signal to
either channel 3 or 4 of a TV set coupled to the modulator 338. The
modulator 338 also allows the combined composite signal to bypass a
cable/antenna input of the TV set. Operations carried out to
display video and graphical images on the TV set screen will be
described in more detail later.
The TV set coupled to the satellite receiver 300 may display
graphics data representing a graphical user interface (GUI) that
allows a user to control operations of the satellite receiver 300,
and provides user access to services and options offered by the
digital satellite TV system. For example, graphics on the TV set
screen may represent a graphical channel changer that enables a
user to select TV channels. Another example of a graphical
presentation on the TV screen is an electronic program guide that
contains names of TV programs arranged in a 2-dimensional array, in
which TV channels are listed vertically, and the time of
broadcasting is listed in the horizontal direction. Various aspects
of the GUI including the graphical channel changer are discussed in
more detail later.
A modem 340 such as a single-chip SSI 1200-baud modem is provided
to support communications via a narrowband port 342 used for low
bandwidth signal transmission, or via a telephone jack connected to
a telephone line. For example, the modem 340 may support remote
billing and interactive services.
A microcontroller 344 such as a Phillips 87593 microcontroller
provides control of receiver functions relating to control,
interface and display devices arranged at the front panel of the
satellite receiver 300. Among such devices are a pointing device
interface 346, front panel controls 348, and a vacuum fluorescent
display (VFD) 350.
The pointing device interface 346 enables a remote optical pointing
device such as an Airmouse.RTM. to provide a wireless control of
the satellite receiver 300. By way of example, reference is made to
U.S. Pat. No. 5,045,843 to Hansen of Sep. 3, 1991, and U.S. Pat.
No. 5,359,348 to Pilcher et al. of Oct. 25, 1994 for descriptions
of Airmouse.RTM. arrangements and operation. For example, the
pointing device interface 346 may comprise infrared (IR)
transmitter and receiver that provide infrared communications with
a pointing device located up to 7 meter away from the receiver 300
at an angle up to 45 degrees. This type of remote pointing device
has been used principally for moving the cursor of a personal
computer.
The Airmouse.RTM. type pointing device in accordance with the
invention points directly at a TV set screen to provide direct
interactions between the user hand that holds the pointing device,
and the TV screen. The pointing device may comprise a cursor
control circuit that moves a cursor on the TV screen in response to
the position of the pointing device with respect to, for example,
the IR transmitter at the front panel of the receiver. The pointing
device interface 346 supports the GUI by providing and controlling
the RF tuner 302 of the satellite receiver to respond to random,
instant user access to any point on the TV screen. Selections are
made by clicking one of the buttons on the pointing device. For
example, at any time when there is no menu on the screen, a first
click provides a basic control bar of menus across the bottom of
the screen. The control menu bar remains active for a preset
period, after which it is made invisible if no further signals from
the pointing device are detected. Interactions between the GUI and
remote pointing device are disclosed in more detail in our
copending application SN 08/720,501, entitled "TELEVISION GRAPHICAL
USER INTERFACE EMPLOYING REMOTE RANDOM ACCESS POINTING DEVICE,"
filed concurrently herewith and incorporated by reference.
In addition to the optical pointing device, a remote hand held
control unit of the satellite receiver 300 may also include several
dedicated buttons to provide, for example, switching power ON and
OFF, channel and volume control, selection between regular TV
broadcasting and satellite broadcasting, etc.
The front panel controls 348 provides control of the GUI in the
event that the remote pointing device is missing or non-operable.
The controls 348 may include a TV/Satellite receiver key for
switching between regular TV broadcasting and satellite
broadcasting. Set-up, menu, clear, select or "click" keys may be
provided to control modes of operation. Cursor keys may be arranged
to move the cursor on the TV screen in various directions.
The VFD 350 is provided to show current TV channel number and time.
Also, the VFD 350 may indicate current incoming signal strength and
other operational information.
Reference is now made to FIG. 2 that illustrates drawing color
graphic objects on a TV screen in accordance with the present
invention. As discussed above, the CPU 318 interacts with the
graphics accelerator 330 used as a co-processor to enhance the
graphics capability of the satellite receiver 300. The CPU 318 may
be coupled to the graphics accelerator 330 via an external 24-bit
address bus 402, and a 16-bit data bus 404. The 24-bit address bus
402 enables the CPU 318 to address up to 16Mbytes of a graphics
memory. This storage capacity corresponds to an address space from
000000 to ffffff in hexadecimal notation. Various graphics memory
arrangements may be organized in this address space, as long as
each memory location is uniquely addressable. For example, the
capacity of the graphics memory 334 may be equal to 4Mbit or
512Kbytes. Assuming that the graphics memory address space
corresponds to the middle part of the system memory map, the
$800000 hex address may be selected as the lowest graphics memory
location, and the $87ffff hex address may be designated as the top
graphics memory address. The graphics memory 334 may be coupled to
the graphics accelerator 330 via memory address lines 406 and
memory data lines 408.
The graphics accelerator 330 enables a TV set to display up to 16
million different colors. However, only 256 different colors can be
displayed on any one screen at any given time. As a result, each
unique pixel displayable on a TV screen can be represented by a
single 8-bit value. Thus, each pixel stored in the 512Kbyte
graphics memory 334 is represented by a single 8-bit value or
byte.
Each graphics plane stored in the graphics memory 334 is provided
by a rectangular array of 720.times.480 pixels representing a
picture on the TV screen. For example, the pixels may be stored in
the graphics memory 334 from top left to bottom right in row order.
Thus, the top left hand pixel of the screen resides at the $800000
hex graphics memory location. The second pixel on the top line 1 is
stored at $800001 hex, etc. The last pixel of the top line 1 is
held at $8002D0 hex. The first pixel of the next line 2 is at the
$8002D1 hex graphics memory location, etc. The bottom right hand
corner of the screen corresponds to the $8545ff location of the
graphics memory 334. Thus, the graphics memory arrangement
corresponds to a rectangular X,Y-coordinate system on the TV
screen, where 720 pixels in each line of the array are arranged in
the horizontal direction X, and 480 pixels in each row of the array
are arranged in the vertical direction Y.
The graphics accelerator 330 contains a color look up table (CLUT)
that converts 256 elements representing 8-bit pixel values stored
in the graphics memory 334 into 24-bit values composed of red (R),
green (G), and blue (B) bytes corresponding to R, G, and B
components of a picture in RGB format. The CLUT may be programmed
by the CPU 318 to reproduce any color possible in a 24-bit color
space.
FIG. 3 illustrates some typical colors reproducible by the CLUT.
For example, black color composed of red, green and blue bytes
represented by $0 hex may correspond to the $0 hex location of the
CLUT. White color composed of the $ff hex red, green and blue bytes
may correspond to the $4 hex CLUT location, etc.
When the CLUT is programmed, the CPU 318 accesses the graphics
memory 334 to write data values representing graphics. The graphics
accelerator 330 scans the graphics memory 334 at a rate of 13.5 MHz
to read the graphics data. Each 8-bit pixel value is transferred to
the CLUT that converts it into a 24-bit color value in RGB format.
As discussed above, the converter 332 converts the RGB color value
into YUV format, and passes a 24-bit digital YUV value to the
digital encoder 322 that converts it into analog NTSC luminance and
chrominance signals, for example, at a 13.5 MHz rate. The NTSC
encoding procedure carried out by the encoder 322 is well known to
those skilled in the art. The analog luminance and chrominance
signals via the TV modulator 338 are supplied to the TV set.
FIG. 4 shows a flow chart that illustrates an example of
interactions between the CPU 318 and graphics accelerator 330 to
draw a 240.times.240 pixel red square in the middle of a TV screen
with a black background. In step 602, the CPU 318 resets the
graphic accelerator 330. In step 604, the CPU 318 programs the CLUT
in the graphics accelerator 330 so as to set CLUT location $0 hex
to reproduce black color, i.e. red, green and blue bytes in this
location are set to $0 hex. In step 606, the CPU 318 sets CLUT
location $1 hex to reproduce red color, i.e. a red byte in this
location is set to $ff hex, and green and blue bytes are set to $0
hex.
In steps 608 and 610, the CPU 318 carries out a loop to make the TV
screen black. Locations $800000+I of the graphics memory 334 are
set to $0 hex, for I that varies from $0 hex to $545ff hex.
In steps 612-622, the CPU 318 performs a double loop to draw the
red 240.times.240 pixel box on the screen. The double loop
comprises an outer loop carried out to set pixels in rows
(Y-direction on the screen) of the graphics memory 334 to $1 hex to
reproduce them in red color, and an inner loop to set pixels in
lines (X-direction) of the graphics memory 334 to $1 hex to
reproduce them in red color.
For example, as shown in FIG. 5, the TV screen may be represented
by a 720.times.480 array of pixels corresponding to a graphics
plane stored in the graphics memory 334. 720 pixels may be arranged
on the screen in the horizontal direction X, whereas 480 pixels may
be arranged in the vertical direction Y. To perform graphics
drawing operations, the CPU 318 may use an X, Y-coordinate system
shown in FIG. 5, wherein coordinates X=0, Y=0 represent the top
left hand corner of the TV screen, and coordinates X=720, Y=480
represent the bottom right hand corner of the screen.
Due to "overscan" conditions, a television receiver may produce a
raster on its screen so that pixels in the horizontal and vertical
directions may not be entirely in the view of the user. Therefore,
TV broadcast systems prevent images from being displayed outside of
a "safe" area located within approximately a 10% border all around
the edge of the screen. As shown in FIG. 5, the safe area contains
approximately 576 pixels in the horizontal direction, and 400
pixels in the vertical direction.
Reference is now made to FIG. 6, that illustrates the TV GUI of the
present invention placed in a channel changer mode for enabling
users to select TV channels. An outer solid-lined box represents
the edge of a TV screen that displays the GUI, and a dash line
shows the border of a safe area on the screen. The TV GUI includes
a graphical channel changer 800 having a vertical channel bar
composed of graphical channel boxes 802 representing TV channels
available in the satellite receiver 300. For example, each box 802
may contain the number and logo of a TV channel. In a digital
satellite TV system, the channel bar may represent about 1,000 TV
channels. A restricted number of the boxes 802 may be displayed on
the TV screen at any given time. For example, FIG. 6 shows that six
boxes 802 representing channels 287-292 are simultaneously
displayed. The vertical channel bar may be represented by
120.times.300 pixels. For example, its top left corner may have
coordinates X=122, Y=90, and its bottom right corner may be
arranged at X=242, Y=390.
To switch the TV set to a required TV channel, the user directs the
pointing device at the graphical channel box 802 that contains the
number and logo of the required channel. A click of the pointing
device button causes the CPU 318 to send a tune command to the RF
tuner 302 for switching the satellite receiver 300 to the required
TV channel.
Up and down scroll bars 804 and 806 are arranged near the channel
boxes 802 to allow a user to scan through the entire list of TV
channels in opposite directions. A single click of the pointing
device button causes the GUI to move up or down by one channel with
respect to the TV channels currently represented in the channel
boxes 802. For example, when the user clicks the pointing device
held in the direction of the up scroll bar 804, the boxes 802 will
shift from channels 287-292 to channels 286-291. If the pointing
device points at the down scroll bar 806, a single click will cause
the boxes 802 to move from channels 287-292 to channels 288-293.
Holding down the pointing device button may cause the list of TV
channels to scroll continuously.
A relative position indicator 808 shows the position of the TV
channels currently displayed in the channel boxes with respect to
the other available TV channels. The relative position indicator
808 is a horizontal strip that determines the boundary between the
up and down scroll bars 804 and 806. When the user causes the
channels in the channel boxes 802 to move up or down, the relative
position indicator 808 also moves up or down.
A direct access bar 810 presented next to the channel boxes 802
causes the GUI to display in the channel boxes 802 numbers and
logos of a selected group of channels when the user clicks the
pointing device directed at the area of the direct access bar 802
that represents the selected group of channels. The direct access
bar 810 comprises a graduated scale representing available TV
channels. For example, as shown in FIG. 6, the channel scale may
represent 1000 TV channels (from channel 000 to channel 999)
provided by the digital satellite TV system 300.
The scroll bars 804 and 806 are extended beyond the safe area to
the edge of the screen. As a result, their size is increased.
Moreover, the screen area is fully utilized, independently of the
overscan conditions.
For example, as indicated by a dash line in FIG. 6, the top left
hand corner of the safe area may be arranged at X=72, Y=40. The
bottom right hand corner of the safe area may have coordinates
X=648, Y=440.
The up scroll bar 804 drawn in accordance with the graphical object
drawing procedure discussed above may be composed of a top section
804A and a bottom section 804B. The bottom right corner of the top
section 804A may be provided at X=122, Y=90. This position may
coincide with the top left point of the top channel box 802. The
top left corner of the top section may be generated at the top left
corner of the screen at X=0, Y=0. As a result, the top section 804A
is extended beyond the safe area in the horizontal and vertical
directions.
The bottom section 804B displayed beneath the top section 804A may
be formed completely outside the safe area. For example, the top
left corner of the bottom section 804B may be selected at X=0,
Y=90, and its top right corner may be at X=72, Y=90.
The down scroll bar 806 drawn in accordance with the graphical
object drawing procedure discussed above may be composed of a top
section 806A and a bottom section 806B.
The bottom section 806B may have its top left corner provided at
the vertical edge of the screen, for example, at X=0, Y=390. Its
bottom right corner may be arranged at the horizontal edge of the
screen, for example, at X=122, Y=480. Thus, the bottom section of
the down scroll bar 806 is extended beyond the safe area in the
horizontal and vertical directions.
The top section 806A may be arranged above the bottom section 806B.
For example, its bottom left corner may be provided at X=0, Y=390,
its bottom right corner may be at X=72, Y=390.
As the top edge of the up scroll bar 804 coincides with the top
edge of the screen, and the bottom edge of the down scroll bar 806
coincides with the bottom edge of the screen, the scroll bar
composed of the up and down scroll bars 804 and 806 appears to wrap
around the screen. As a result, the up and down scroll bars are
made large enough to facilitate user access to these graphical
control buttons during channel selection. Moreover, the screen area
is fully utilized independently of the overscan conditions.
In accordance with the present invention, the up scroll bar 804 and
down scroll bar 806 dynamically alter their size when a user scans
through a list of available TV channels by pressing a button on a
pointing device held in the direction of the up scroll bar 804 or
down scroll bar 806. In particular, when the user directs the
pointing device at the up scroll bar 804 to move up through the
channels, the GUI makes the up scroll bar 804 shorter and the down
scroll bar 806 longer. By contrast, when the user points at the
down scroll bar 806 moving down through the list of available
channels, the GUI makes the up scroll bar 804 longer, and the down
scroll bar 806 shorter. As a result, the user is provided with
visual feedback that shows the relative position of the TV channels
currently displayed in the channel boxes 802 with respect to the
channel list. For example, when in a 1000 channel TV system, the
user moves through channel 500, the up scroll bar 804 and down
scroll bar 806 have the same size implying that there are as many
channels above the current position in the channel list as below
the current position. As discussed above, the top section 804A of
the up scroll bar 804, and the bottom section 806B of the down
scroll bar 806 may be maintained fixed. The bottom section 804B of
the up scroll bar 804, and the top section 806A of the down scroll
bar 806 alter their size in the vertical direction along the
Y-axis. Their size in the horizontal direction along the X-axis may
be maintained fixed.
For the sake of discussion, it is assumed that the relative
position strip 808 arranged between the up and down scroll bars 804
and 806 has zero width. In reality, the width of the strip 808 is
equal to a few pixels.
Then, if there are 1000 channels of programming available, and the
relative position indicator 808 is positioned at channel 300, the
bottom section 804B of the up scroll bar 804 stretches from Y=90 to
Y=180, whereas the top section 806A of the down scroll bar 806
stretches from Y=180 to Y=390. Thus, the bottom section of the up
scroll bar 804 has 90 pixels in the vertical direction, and the top
section of the down scroll bar 806 includes 210 pixels.
As the system scrolls, the relative size of the up and down scroll
bars 804 and 806 changes. For example, if the user directs the
pointing device at the down scroll bar 806 to scroll down by 100
channels, the relative position indicator 808 will be at channel
400. In this case, the bottom section of the up scroll bar 804 is
generated from Y=90 to Y=210, and the top section of the down
scroll bar 806 is provided from Y=210 to Y=390.
Thus, the bottom section of the up scroll bar 804 elongates from 90
pixels to 120 pixels, and the top section of the down scroll bar
806 shortens from 210 pixels to 180 pixels.
As the user scrolls down by another 100 channels, the relative
position indicator will be at channel 500. The bottom section of
the up scroll bar 804 will stretch from Y=90 to Y=240, and the top
section of the down scroll bar 806 will be positioned between Y=240
and Y=390. Thus, the up scroll bar 804 will further elongate by 30
pixels, and the down scroll bar 806 will further shorten by 30
pixels.
Reference is now made to FIG. 7 that illustrates operations carried
out in accordance with the present invention to dynamically change
sizes of the up and down scroll bars 804 and 806. In step 902, the
pointing device held in the user's hand causes the cursor to move
to the up or down scroll bar 804 or 806. Coordinates of the
pointing device may be supplied to the microcontroller 344 on a
periodic basis, for example, 60 times a second. In response, the
CPU 318 samples the cursor positions to generate X, Y coordinates
corresponding to a path for moving the cursor in alignment with
pointing device movement. Cursor movement is achieved by multiple
erasures and redraws of the cursor image performed on the path to
the selected area. In step 904, the CPU 318 determines whether or
not the cursor is inside one of the scroll bars 804 and 806. If so,
the color of the corresponding scroll bar changes to indicate that
the scroll bar is active (step 906). If no cursor inside the scroll
bars 804 and 806 is detected, the CPU checks for cursor in the
other areas of the GUI (step 908) and returns to sampling the
cursor positions in step 902.
When a required cursor position inside the scroll bar 804 or 806 is
reached, the user may press a select button on the pointing device.
In step 910, the CPU 318 checks whether or not the select button is
pressed. If so, the CPU 318 determines a value P that defines
increment or decrement of the position of one of the scroll bars
804 and 806 relative to the position of the other. For example, if
the down scroll bar 806 is activated to scroll down from channel
300 to channel 400, increment by 100 channels is detected. Thus,
the value P is determined to be 100. If the decrement is detected,
the value P is negative.
In step 914, the CPU 318 determines a value Y that defines a new
Y-coordinate of the relative position indicator 808. For example,
in a 1000 channel TV system, where the bottom section of the up
scroll bar 804 and the top section of the down scroll bar 806 have
300 pixels in the vertical direction, if the old Y-coordinate of
the relative position indicator 808 is 90 (the indicator set at
channel 300), the value Y may be determined as
Y=90+300.times.P/1000.
Based on the new Y-coordinate determined in step 914, the relative
position indicator 808 is redrawn (step 916). Then, in step 918,
the up scroll bar 804 is redrawn so as to arrange it above the
relative position indicator 808. In step 920, the down scroll bar
806 is redrawn so as to arrange it below the relative position
indicator 808. In step 922, channel logos and numbers displayed in
the channel boxes 802 are redrawn to represent the channels
indicated by the new position of the relative position indicator
808. The graphical objects on the screen are redrawn in accordance
with the graphical object drawing procedure discussed above in
connection with FIGS. 3 and 4.
There accordingly has been described a TV graphical user interface
that includes a graphical channel changer for enabling a user to
select a required TV channel among about 1000 channels provided by
a satellite TV system. The graphical channel changer contains a
vertical channel bar composed of channel boxes that display numbers
and logos of selected TV channels. To switch the TV set to a
required TV channel, the user directs the pointing device at the
graphical channel box that indicates the required channel, and
presses select. Up and down scroll bars, that allow the user to
scan through the entire list of TV channels, extend beyond a safe
area provided on a TV screen. The up and down scroll bars
dynamically alter their size in accordance with the position of the
subsequence of TV channels currently displayed relative to the
entire sequence of TV channels representing the domain of choice,
to provide the user with visual feedback. A relative position
indicator is arranged between the up and down scroll bars.
In this disclosure, there are shown and described only the
preferred embodiments of the invention, but it is to be understood
that the invention is capable of changes and modifications within
the scope of the inventive concept as expressed herein.
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